Fullerene-capped copolymers for bulk heterojunctions: device stability and efficiency improvements

Mahfoudh Raïssi (1) , Harikrishna Erothu (2, 3) , Emmanuel Ibarboure (2) , Henri Cramail (2, 3) , Laurence Vignau (1) , Eric Cloutet (2, 4) , Roger C. Hiorns (5)

1 IMS - Laboratoire de l'intégration, du matériau au système
2 LCPO - Laboratoire de Chimie des Polymères Organiques
3 Team 2 - U1064 Inserm - CRTI - Genetic and Cellular Engineering in Immunology and Regenerative Medicine
4 Team 4 LCPO : Polymer Materials for Electronic, Energy, Information and Communication Technologies
5 IPREM - Institut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux

A fullerene end-capped polymer-compatibilizer based on poly(3-hexylthiophene) (P3HT) was synthesized and demonstrated to have a remarkable effect on both the stability and efficiency of devices made from exemplar P3HT and [6,6]-phenyl C61-butyric acid methyl ester (PCBM). P3HT with ethynyl chain-ends and -azido--bromo-PS were prepared via Grignard metathesis (GRIM) and atom transfer radical polymerisations, respectively. “Click” chemistry resulted in the preparation of poly(3-hexylthiophene)-block--bromo-polystyrene (P3HT-b-PS-Br), and subsequent atom transfer radical addition chemistry with fullerene (C60) yielded the donor-acceptor block copolymer P3HT-b-PS-C60. Both P3HT-b-PS-Br and P3HT-b-PS-C60 were considered as compatibilizers with P3HT/PCBM blends, with the study detailing effects on active-layer morphology, device efficiency and stability. When used at low concentrations, both P3HT-b-PS-Br (1%) and P3HT-b-PS-C60 (0.5%) resulted in considerable 28% and 35% increases in efficiencies with respect to devices made from P3HT/PCBM alone. Furthermore, P3HT-b-PS-C60 (0.5%) resulted in an important improvement in device stability.

Mots clés: ORGANIC PHOTOVOLTAICS; MORPHOLOGY; POLY(3-HEXYLTHIOPHENE); PERFORMANCE; COIL BLOCK-COPOLYMERS; POLYMER SOLAR-CELLS; MOLECULAR-WEIGHT DISTRIBUTIONS; CLICK-CHEMISTRY; ROD-COIL; PHOTOVOLTAIC APPLICATIONS

Domaines: Polymères

Mahfoudh Raïssi, Harikrishna Erothu, Emmanuel Ibarboure, Henri Cramail, Laurence Vignau, et al.. Fullerene-capped copolymers for bulk heterojunctions: device stability and efficiency improvements. Journal of Materials Chemistry A, 2015, 3 (35), pp.18207-18221. ⟨10.1039/C5TA02705E⟩. ⟨hal-02922653⟩